Ergon GA1 or GE1 with bar ends?

Weight question I know, but I've got a couple sets of Ergon grips currently (GX2 and GR2) and while I love the bar ends and the feels of the grips, I can't seem to adjust the wing so that I don't get hand numbness on rides over 45 minutes or so.

This is despite a LOT of tweaking and even trying different gloves.

So, I was thinking of picking up a set of the slimmer, more round, GA1 grips.

My question is, can I slide off the grip locking end and put the bar end from a Gx2 or GR2 on there in it's place? The grips are only $30, so i guess it wouldn't cost me too much to find out.

I found a post where someone was claiming to use a GR2 bar end on a GE1 grip, so perhaps it is possible.